Medical kit comprising a catheter, a needle and its case

ABSTRACT

A sheath is provided with a stationary deflector disposed on the path of the slider so that contact between the slider and the deflector causes the slider to be inclined and consequently causes the needle to be inclined inside the sheath. A return mechanism is provided so as to push the inclined slider back in the opposite direction so that the point of the inclined need is prevented from moving. This disposition ensures that the needle cannot escape from the sheath after it has been used.

[0001] The invention relates to a medical assembly comprising a shortcatheter, a puncturing needle engaged in the catheter to enable thecatheter to be inserted into a body, and a tubular sheath detachablycoupled to the catheter to receive the entire needle after the needlehas been used for puncturing and once it has been withdrawn from thecatheter.

[0002] Numerous embodiments of such an assembly are known (U.S. Pat. No.5,273,540, U.S. Pat. No. 6,077,244, U.S. Pat. No. 6,193,690, U.S. Pat.No. 5,879,331, WO 95/19193).

[0003] Publications U.S. Pat. No. 5,879,331 and WO 95/19193 describeembodiments in which the sheath presents a longitudinal slot between adistal outlet for connection to the catheter and an opposite proximalend, and carries a slider mounted to slide along the slot, the sliderpresenting an internal portion situated inside the sheath andconstituting a base for the needle, and an external portion situated onthe sheath and enabling the slider to be moved manually so as to causeit to slide from a distal position in which the needle passes throughthe catheter to a proximal position in which the needle is totallywithdrawn from the catheter and retracted into the sheath.

[0004] The problem arises of ensuring that once the needle has beenretracted into the sheath in this way and after the sheath and thecatheter have been separated, it is not possible under the effect ofinappropriate handling of the slider for the needle to be moved back outfrom the sheath through the coupling outlet, and various solutions havebeen proposed for this purpose.

[0005] In the solution described in U.S. Pat. No. 5,879,331, the sheathis provided with a moving arm which tilts when it is contacted by theslider, and presses against the needle close to its sharp end so as toincline the needle in such a manner that it is no longer on the axis ofthe catheter coupling outlet.

[0006] In an embodiment described in publication WO 95/19193 the sheathis shaped internally, close to the end of the stroke of the slidertowards said proximal end of the sheath, so that, at the end of thestroke, contact between the slider and the sheath causes the slider tobe inclined and consequently causes the needle to be inclined inside thesheath.

[0007] The present invention seeks to provide anti-pricking safety whilesimplifying the device and reducing its overall dimensions.

[0008] The invention achieves this by providing a stationary deflector(13; 16; 22) disposed inside the sheath on the path of the slider closeto the end of the stroke of the slider towards said proximal end (3 b)of the sheath, so that contact between the slider and the deflectorcauses the slider to be inclined and consequently causes the needle tobe inclined inside the sheath, and return means designed forsubsequently pushing the inclined slider back towards the distal end ofthe sheath so that the tip of the needle is prevented from moving.

[0009] The return means are preferably constituted by means provided onthe slider and means provided on the sheath, said means being disposedso as to come into contact at the end of the stroke of the slidertowards said proximal end, and cooperating so that the slider is pushedback in the opposite direction by a resilient effect.

[0010] Preferably, the tip of the inclined needle is pushed back untilit becomes set in the wall of the sheath or in the wall of a couplingmounted at the distal end of the sheath.

[0011] Preferably, the tip of the inclined and pushed-back needle isreceived in a groove made around the needle outlet of the sheath.

[0012] Non-limiting embodiments of an assembly of the invention aredescribed below by way of example with reference to the figures of theaccompanying drawings, in which:

[0013]FIG. 1 is a diagram showing the various states of a firstembodiment during successive stages A to F of withdrawing the needleinto the tubular sheath;

[0014]FIG. 2 is a diagram on a larger scale of the proximal end of thetubular sheath during stages D, E, and F in FIG. 1;

[0015]FIG. 3 is a diagram showing the various states of a secondembodiment during successive stages A to F of withdrawing the needleinto the tubular sheath;

[0016]FIG. 4 is a diagram on a larger scale of the proximal end of thetubular sheath during stages D, E, and F of FIG. 3;

[0017]FIG. 5 is a diagram of the various states of a third embodimentduring successive stages A to F while withdrawing the needle into thetubular sheath;

[0018]FIG. 6 is a diagram on a larger scale of the proximal end of thetubular sheath during stages D, E, and F of FIG. 5;

[0019]FIG. 7 is a diagram of successive stages while implementing anassembly of the invention;

[0020]FIG. 8 is a diagram comparable to that of FIG. 7 for a variantimplementation process;

[0021]FIG. 9 is a diagram corresponding to FIG. 7 for another variantimplementation;

[0022]FIG. 10 is a right section through the main part of the sheath ona plane X-X;

[0023]FIG. 11 is an axial section on a larger scale of the proximal endof the sheath of FIG. 1 with its stopper which is shown separated in thefigure for reasons of clarity;

[0024]FIG. 12 is an axial section on a larger scale of the distal end ofthe sheath in an embodiment in accordance with FIG. 1F, 3F, or 5F;

[0025]FIG. 13 is a right section through a slider and a sheath of theinvention; and

[0026]FIG. 14 is a diagram of the various states of a fourth embodimentduring successive stages A to D while withdrawing the needle into thetubular sheath.

[0027] The assembly shown in the figures comprises a short catheter (1),a puncture needle (2) for enabling the catheter to be inserted into avein, a cylindrical sheath (3) connected detachably to the catheter, anda slider (4) slidably mounted on the sheath so as to withdraw the needleinto the tube after puncturing.

[0028] The sheath (3) has a distal end (3 a) arranged or provided with acoupling (19) for connecting it to the catheter, an opposite proximalend (3 b), and a longitudinal lateral slot (3 c) situated between itsends. The sheath carries the slider (4) mounted to slide along the slotand presenting an external portion (4 a) situated on the sheath and aninternal portion (4 b) situated inside the sheath, these two portionsbeing connected to each other through the slot in the sheath.

[0029] The external portion (4 a) is designed to enable the slider to bepushed so as to slide along the slot.

[0030] The internal portion (4 b) is fixed to the needle and constitutesa hollow base for the needle which is closed by an air-vent filter (5)and which is fitted with a valve which opens under the injectionpressure of a syringe.

[0031] In the examples shown, the external portion (4 a) of the sliderpresents a transverse lug (6) which the user can drive in various waysin order to perform puncturing and subsequently to withdraw the needle,as shown in FIGS. 7 to 9.

[0032] The catheter is provided with a socket coupling (7) of knowntype, and the distal end (3 a) of the sheath is designed to penetrateinto said coupling or is provided with a suitable coupling (19).

[0033] The catheter coupling presents an external bead (8) placed behindthe coupling and the distal end (3 a) of the sheath or the coupling (19)of the sheath presents a forwardly-directed tongue (9) which takes up aposition on the coupling in front of the bead when the base is connectedto the catheter, but which is sufficiently flexible to be capable ofbeing forced over the bead when the sheath is separated from thecoupling.

[0034] The distal end or the distal coupling (19) of the sheath isnormally closed by a transverse partition (10′) which allows the needleto pass axially therethrough, e.g. via a hole (11).

[0035] The catheter coupling (7) may have a lateral inlet (12) inconventional manner for enabling injections to be performed. This inlet(12) is closed by a cap (12′).

[0036] The tubular sheath has stationary deflectors for moving theneedle away from its axis after it has been withdrawn into the sheath,so as to ensure that the needle cannot move back out through the distalend of the sheath under inappropriate handling of the slider.

[0037] In the embodiment of FIGS. 1 and 2, these deflectors areconstituted by a ramp (13) formed on a piece (14) engaged in theproximal end (3 b) of the sheath and prevented from moving by a stopper(14′). This piece is frustoconical in shape, for example, with itsconical wall constituting the ramp. The slider is provided in itsinternal portion with a resilient tongue (15) directed rearwards andwhich causes the slider to be deflected on making contact with the ramp,thereby moving the needle off axis (FIGS. 1D, 1E) as the slider engagesthe ramp.

[0038] At the end of the stroke, the slider is pushed back in theopposite direction by the tongue so that the chamfered tip of theinclined needle (2 a) is received in a cylindrical groove (10) formedinside the distal end (3 a) of the sheath around the outlet (11) untilit becomes set against the wall (10′) at the front of the sheath,thereby preventing the needle from moving (FIG. 1F and FIG. 12).

[0039] In the embodiment of FIGS. 3 and 5, a ramp (16) is formed by aninternal projection on the side wall of the sheath close to the proximalend (3 b) of the sheath and located on the path followed by the internalportion (4 b) of the slider so that the projection causes the slider tobe inclined as it passes over the projection (FIGS. 3D, 3E, 5D, 5E). Ahelical spring (17) placed between the internal portion of the sliderand an abutment (18) situated in the proximal end (3 b) of the sheaththen pushes the slider back sufficiently for the chamfered tip of theneedle to become fixed in the wall (10′) situated at the front of thesheath (FIGS. 3F, 5F, and 12).

[0040] The spring (17) is fixed to the abutment (18) as shown in theembodiment of FIG. 3, or else it is fixed to the internal portion of theslider, as in the embodiment of FIG. 5.

[0041] The abutment (18) is constituted by the front face of a piece(18′) inserted as a stopper into the proximal end of the sheath.

[0042] FIGS. 7 to 9 show successive stages (P1 to P5) in a process ofputting a catheter into place, during which the operator uses one handor both hands to act on the lug (6) of the slider, the cap (12′) of thecoupling, or the stopper (14′), in order to puncture the skin (P1, P2),progressively withdraw the needle (P3, P4), and separate the sheathcontaining the needle (P5) from the catheter coupling.

[0043] In the embodiment in FIG. 14, the return means for returning theinclined needle towards the distal end of the sheath comprises a rigidlug (20) projecting towards the proximal end of the sheath over theinner portion (4 b) of the slider (4) which constitutes the base of theneedle, and a resilient blade (21) disposed in the cross-piece of theproximal end (3 b) of the sheath (3) so that said blade, pushed by thelug, after deflection of the needle (FIG. 14C) and after the user hasrelaxed traction on the slider, pushes the slider back in the oppositedirection over a distance that is sufficient for the point of the needleto be received in a wall of the distal end of the sheath or of thecoupling (19) present at said end (FIG. 14D). For example, it is blockedin the end wall of a cylindrical groove (10) formed in the couplingmounted at the distal end of the sheath in order to connect thecatheter.

[0044] Preferably, as in the example shown, the resilient blade isconstituted by a wall that is molded integrally with the wall of thesheath, but which is secured to the side wall of the sheath over only aportion of its circumference.

[0045] In the embodiment in FIG. 14, the deflector means are constitutedby a ramp (22) that is injection molded integrally with the longitudinalwall of the sheath (like the ramp 16 of the embodiment in FIGS. 3 and 5)and with the resilient blade (21) which is secured to the end of saidramp and is not connected anywhere else with the tube.

[0046] It should be noted that this embodiment is particularly simple.

[0047] The invention is not limited to the embodiments described above.

1. A medical assembly comprising a short catheter, a puncturing needleengaged in the catheter to enable the catheter to be inserted into abody, and a tubular sheath detachably coupled to the catheter to receivethe entire needle after the needle has been used for puncturing and onceit has been withdrawn from the catheter, the sheath presenting alongitudinal slot between a distal outlet end for coupling to thecatheter and an opposite proximal end, and carrying a slider mounted toslide along the slot to control said withdrawal of the needle, theslider presenting an internal portion situated inside the sheath andconstituting a base for the needle, and an external portion situated onthe sheath and enabling the slider to be pushed manually to cause to itto slide towards said proximal end to a proximal position in which theneedle is fully withdrawn into the tube, the sheath comprising astationary deflector disposed inside the sheath on the path of theslider close to the end of the stroke of the slider towards saidproximal end of the sheath, so that contact between the slider and thedeflector causes the slider to be inclined and consequently causes theneedle to be inclined inside the sheath, the assembly beingcharacterized in that return means are provided so as to push theinclined slider back in the opposite direction so that the point of theinclined need is prevented from moving.
 2. An assembly according toclaim 1, in which the distal end of the sheath presents a groove madearound a needle outlet of the sheath to receive the tip of the inclinedneedle.
 3. An assembly according to claim 2, having a groove that isformed in a coupling disposed in said distal end for connecting thecatheter.
 4. An assembly according to claim 1, in which the deflector isconstituted by a piece disposed in the proximal end of the sheath.
 5. Anassembly according to claim 1, in which said deflector is constituted bya piece engaged and held in the proximal end of the sheath and presentsa ramp on which an internal portion of the slider becomes engaged.
 6. Anassembly according to claim 5, in which the internal portion of theslider presents a resilient tongue which rubs against said ramp andwhich acts at the end of the slider stroke to push back the inclinedslider.
 7. An assembly according to claim 1, in which the deflector is aramp constituted by an internal projection from the side wall of thesheath.
 8. An assembly according to claim 7, and including a helicalspring disposed between the internal portion of the slider and anabutment disposed in the proximal end of the sheath to push the inclinedslider back at the end of its stroke.
 9. An assembly according to claim8, in which said spring is fixed to the internal portion of the slider.10. An assembly according to claim 8, in which said spring is fixed tosaid abutment.
 11. An assembly according to any claim 7, in which theabutment is the front face of a stopper inserted in the proximal end ofthe sheath.
 12. An assembly according to claim 1, in which said returnmeans are constituted by a rigid lug projecting towards the proximal endof the sheath over the inner portion of the slider and by a resilientblade disposed at the proximal end of the sheath so that said blade,pushed by the lug, after inclination of the needle, pushes the sliderand the needle back in the opposite direction over a distance that issufficient for the point of the inclined needle to be blocked in thedistal end of the sheath.
 13. An assembly according to claim 12, inwhich said distal end of the sheath is provided with a coupling formounting the catheter, and in which said coupling presents, around theneedle outlet of the sheath, a groove for receiving the point of theinclined and pushed-back needle.
 14. An assembly according to claim 12,in which said resilient blade is formed by a wall situated in thecross-piece of the proximal end of the sheath, but which is secured tothe sheath only over a portion of its circumference.
 15. An assemblyaccording to claim 12, in which the sheath comprises deflector meansconstituted by a ramp constituted by an inside bulge of the side wall ofthe sheath, and in which said wall which constitutes the resilient bladeis injection molded integrally with the end of said ramp.
 16. Anassembly according to claim 1, in which the short catheter is providedwith an inlet coupling which serves as a thrust bearing point for theuser in which the distal end of the coupling of the sheath to thecatheter is shaped in order to penetrate into said coupling and tosecure said end to the coupling.
 17. An assembly according to claim 16,in which the distal end of the sheath is provided with a coupling forconnecting it to the catheter, which coupling penetrates into thecatheter coupling.